A motor control center is a multi-compartment enclosure comprising a power bus system to distribute electrical power, on a common bus system, to one or more motor control units within the motor control center sections. The motor control units are typically constructed to be removable units that have individual sealed doors on the motor control center section. These motor control units may contain various motor control and motor protection components, such as motor controllers, starters, contactor assemblies, overload relays, circuit breakers, motor circuit protectors, various disconnects, and similar devices for electric motors. The motor control units connect to the supply power lines of the motor control center and supply power to the line side of the motor control devices, for operation of motors. Motor control centers are oftentimes used in factories and industrial facilities which utilize high power electrical motors, pumps, and other loads.
Typically, when installing or removing motor control units, the power supply lines are connected. To remove the motor control units, a door of the motor control unit or motor control center section is opened and an operator manually pulls the motor control unit to separate the conductive contacts or stabs from the bus system, thereby disconnecting the power supply. Installation of a motor control units are accomplished in a similar manner, whereby the operator manually pushes the bucket into a compartment of the motor control center section to engage the stabs with the bus system, thus connecting the system to supply power. In some instances, the stabs may be difficult to maneuver manually (push and pull) when an operator is supporting the entire bucket or when the stabs are not visible. These difficulties may lead to numerous hazards (e.g., shocks/misfires, an arc or arc flash) that may be harmful and dangerous to the operators. It would therefore be desirable to design, manufacture and assemble a motor control unit that overcomes the aforementioned difficulties.